Levulinic acid ester



Z 1 UNITED STATES PATENT OFFICE LEVULINIC AClD ESTER Walter E. Lawson and Paul L. Salzberg, Wilmington, Del., assignors to E. .I. du Pont de Nemours & Company, Wilmington, Del., a corporation of Delaware No Drawing. Application May 3, 1932, Serial No. 609,029

9 Claims. (01. 260-106) This invention relates to new esters, their methterials. The product was then. vacuum distilled, d of preparation, and more particularly, the in- 53.5 grams of stearyl levulinate distilling between vention relates to high boiling point levulinic 180-200 C. at 1.5 mm. pressure. esters of monohydric alcohols. Example 3Benzyl teammate-A mixture of '5 Heretofore, a few isolated levulim'c esters of 54 grams of benzyl alcohol, 58 grams of levuiinic -5 the lower aliphatic alcohols were known but had acid and 4 drops of concentrated hydrochloric not been of any practical use. acid was heated at 160-170" C. for 14 hours under An object of the present invention is the prepan air condenser which allowed the water vapor aration of high boiling point levulinic esters of to escape but condensed the other materials. The

monohydric alcohols and the provision of new product was then vacuum distilled, the benzyl l0 plasticizers for cellulose derivatives having great levulinate distilling between 160-170 C. at 8 mm.

patibility with the cellulose derivatives, topressure.

gether with extremely low vapor pressures and The above examples merely illustrate sp cific water insolubility. Other objects of the invenmethods of preparingspecific esters of the gention will be apparent from the description given eral class of esters coming within the scope of hereinafter. this invention. The proportion of'levulinic acid The above objects are accomplished according to alcohol may, oi. course, be varied widely to the present invention by reacting levulinic acid though it is preferred to employ an excess of the with a monohydric alcohol adapted to give a corlevulinic acid above stoichometric proportions.

responding levulinic ester having aboiling point The present invention is broadly app to 20 a in excess of 225 C. at 760 mm. pressure, isolating the preparation of levulinic acid esters of monothe ester, and formulating it in cellulose derivahydric alcohols adapted to' give esters having ti ve compositions. I boiling points in excess of 225 C. Amflng the The reaction of the levulinic acid with the alcohols suitable for this purpose may. be menmonohydric alcohol may be carried out at a temtioned, as well as those given in the specific ex- 25 perature sufficiently high so that the water formed ampl s, the aliphatic alcohols havin m in the reaction is removed substantially as it is carbon atoms, inclusive, such as heptyl, octyl, formed, and/or by employing a catalyst, and/or nonyl, decyl, ceryl, myricyl, et cetera, and other a solvent such as benzene or toluene to aid in the alcohols such as cyclohex'anol, phenylethanol,

removal of the water. An inert gas such as carcetyl alcohol, ethylene chlorhydrin, ethyl lactate, 30 bon dioxide may also be passed through the rephenols,ketobutanol, oleyl-stearyl alcohol mixaction mixture to aid in the removal of the wature; butanolamine, geraniol, carnaubyl, melissyl, ter. It is preferred to keep the temperature beundecylenyl, oleyl, erucyl, propargyl, heptadienyl, tween 80-250 0., depending to some extent on 'butadienyl, exylenyl, methylcyclohexyl, dimethylthe boiling point of the alcohol being used. As cyclohexyl, decahydr-onaphthyl, ienchyl alcohols, 35 suitable catalysts may be mentioned hydrochloric citronellol, linalool, terpineol, menthol, borneol, acid, sulphuric acid, aryl-sulphonic acids, such and isobo'rneol. as p-toluene-sulphonic acid, alcoholates such as All of these esters are either water white liquids sodium alcoholate, and zinc chloride. having boiling points above 225 C. at 760 mm., or

40 The-following examples are given to illustrate white crystalline solids also having boiling points 40 the preparation of esters according to the present above 225 C. at 760 m wh n P They are invention:- immiscible or insoluble in water and are readily Example 1--Lauryl ZevuZinate.A mixture of soluble in the ordinary solvents such as alcohols, 49.6 grams of lauryl alcohol and 31.0 grams of ketones and esters. They have extremely low valevulinic acid was heated at -200" C. for 'six por pressures and are compatible in equal 'pr r- 45 hours under an air condenser which allowed the tions with cellulose nitrate and in equal or lower water vapor to escape but condensed t oth proportions with other cellulose esters and ethers, materials. The resulting product was distilled in such as cellulose acetate, crotyl cellulose, benzyl vacuo, 59 grams distilling between -190 C. at cellulose, ethyl cellulose, cellulosepropionate, and 50 5 mm. pressure. the like. The levulinic esters of the present in- 50 Example 2-Stearyl Zevulinate.-A xt of vention are particularly advantageous for use with 50 grams stearyl alcohol and 21.5 grams of cellulose acetate, since the ketone group of the levulinic acid was heated at 200 C. for about levulinic acid enhances the solubilizing action on eight hours under an aircondenser which allowed this derivative and these particular esters are 55 water vapor to escape but condensed other macompatible in high amounts; However, it will be seen fromthe discussion of the properties of this class of esters that they are all highly suitable for use as plasticizers in all types of cellulose derivative compositions, cellulose derivative compositions containing the esters as plasticizers giving films which are tough and flexible and retain their flexibility substantially indefinitely due to the very low vapor pressures of the esters. Due to the water insolubility ofthe esters, the water resistance of the films is also improved.

Coating compositions prepared using the esters of the present invention give tough, flexible films of good water resistance. In cellulose derivative compositions comprising the plasticizers of the present invention other materials may beused such as damar, ester gum, 'polyhydric alcoholpolybasic acid resins, etc., pigments; fillers, and. plasticizers known to the art.

The esters of the present invention may be used in the preparation of all types of cellulose derivative compositions; in particular they may be used in the preparation of lacquers for coating metal and wood, dopes for coating fabrics, and the like,

and in plastic compositions to be used in the preparation of toilet ware, novelties, sheeting, rods, tubes, et cetera. These esters are also extremely valuable for use as plasticizers in blasting powders, and the like.

Among the advantages of the present inVention are that it furnishes water resistant plasticizers for cellulose derivatives. Another advantage is that they are muchmore compatible with cellulose acetate than ordinary plasticizers and, due to their low vapor pressure, they give products which are substantially permanently flexible and have excellent durability.

As many apparently widely different embodimerits of this invention maybe made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.

We claim:

1. Process comprising heating levulinic acid and a monohydric open chain aliphatic alcohol having from '7 to 18 carbon atoms, inclusive, to reaction temperature, and removing the water formed by said reaction from the reaction zone at substantially the rate it is formed. -2. Process of claim 1 wherein the alcohol is lauryl alcohol.

3. Process of claim 1 wherein the alcohol is stearyl alcohol.

4. Process comprising reacting levulim'c acid and a monohydric open chain aliphatic alcohol having from 7 to 18 carbon atoms, inclusive, pressure, at 80-250 C., and removing the water formed by said reaction from the reaction zone at substantially the rate it is formed.

5. Process comprising reacting levulinic acid and a monohydric open chain aliphatic alcohol having from 7 to 18 carbon atoms, inclusive, at 80-250 C. in the presence of a catalyst, and removing the water formed by said reaction from the reaction zone at substantially the rate it is formed.

6. Process comprising reacting levulinic acid and a monohydric open chain aliphatic alcohol having from 7 to 18 carbon atoms, inclusive, at 80-250 C. in the presence of a relatively volatile solvent for the reaction mixture, and removing the water formed by 'said reaction from the reaction zone at substantially the rate it is formed.

7. As a new compound, a levulinic ester of a. monohydric open chain aliphatic alcohol having from 7-18 carbon atoms, inclusive.

8. As a new compound, lauryl levulinate.

9. As a new compound, stearyl levulinate.

' WALTER E. LAWSON.

PAUL L. SALZBERG.

CERTlFlCATE or CGRRECTION. iatent No. 2,008,720. July 23, 1935.

WALTER E. LAWSON, ET AL.

It is hereby certified that error appears in the printed s ecification 0% the above numbered patent requiring correction as follows: Page 2, second column, line 16-17, claim 4, strike out the word and comma "pressure,"; and that the said Letters Patent should be read with this correction therein that the same may cenform to the record of the case in the Patent Office.

Signed and sealed this 1 7th day of September, A. D. 1935.

Leslie Frazer Acting Commissioner of Patents. 

